This is a rare photograph of the mystery-shrouded exterior of Brooklyn's only superhero supply store. Want to see what they have inside?

If you're extra lucky, they'll let you into a secret lair (behind a bookshelf, of course). Earlier this year, we wrote about the products available from the store, and now we're bringing you inside. The Brooklyn Superhero Supply is yet another whimsical concept store from novelist Dave Eggers, who runs a series of writing workshops for young people in these storefronts - which include San Francisco's Pirate Store, and a Time Travel Mart in Los Angeles. Eggers' nonprofit 826 National is devoted to teaching kids to write by inspiring them with imaginative scenarios and general fun.